Clock driving mechanism



Oct. 25, A, F, P E 1,884,853

CLOCK DRIVING MECHANISM Original Filed April 4, 192.7 3 Sheets-Sheet l Fyj L ARTHUR FPO0LE INVENTOR'.

A TTORNE Y.

OCL 25, 1932. A POOLE 1,884,853

CLOCK DRIVING MECHANISM 3 Sheets-Sneak 2 Original Filed April 4, 1927 ARTHUREPOOLE INVENTOR.

ATTORNEY.

Oct. 25, 1932- A. F. POOLE 1,884,853

I CLOCK DRIVING MECHANISM Original Filed April 4, 1927 3 Sheets-Sheet 5 llllll ARTHUZ? 1YPO0LE IN VEN TOR.

A TTORNE Y.

Patented Oct. 25, 1932 UNITED STATES PATENT OFFICE ARTHUR F. POOLE, OF ITHACA, NEW YORK, ASSIGNOR TO POOLE MANUFACTURING CO INC., OF ITI-IACA, NEW YORK, A CORPORATION OF NEW YORK CLOCK DRIVING MECHANISM Original application filed April 4, 1927, Serial No. 180,830, new Patent N'o. 1,831,260, dated November 10, 1931. Divided and. this application filed October 12, 1928. Serial No. 312,089.

:tion relates to clock mechanisms, arly to impulse receiving or drive devices. This application is a division my copending application Serial No. 0,830, electric clock mechanism, filed April 4-. la which issued as Patent No. 1,831,260, Nov. 10. 1931, and relates to such portions as the driving mechanism and impulse devices for the pendulum. which While illustrated in "r preferred embodiment in an electric l are not necessarily restricted thereto. This invention has for its objects the provision of a simple and accurate clock driving mechanism, in which the power is applied to t me deteini'ning element in small periodic impulses of definite force. Other objects are to 'eve the escapement wheel or" the load the pendulum; to maintain the i ogth of the periodic impulses substantialclent of the ordinary variations in force; to prevent damage to the chanism thru careless handling of and various other objects as trent, all with a view to producing a simple, practical and accurate clock .acchanism.

riving me s forming part of this speciatmg one embodiment of 3 lo elevation of an electric clock .owing the general relation of 'cal construction.

l d elevation of the clock actuatin mechanism taken on the line 22 of Fig. 1, looking in the direction of the arrows, showing the relation of the parts at the momen the el ctric contact is broken, and the driving impulse is being delivered to the pendulum.

F 3 is a somewhat similar elevation of the clock actuating mechanism as viewed from the rear, illustrating the relation of the parts at the moment when the electric contact is being made, and before the actuation of the driving mechanism.

Fig. 4 is a detail view showing one form of the driving spring, yieldable crutch and pallet holding mechanism.

Fig. is a. cross-section of the second crutch mechanism, the section being taken on the line 5-5 of Fig. 2, looking in the direction of the arrows.

Fig. 6 is a detail side elevation of the crutch mechanism, one form of pendulum support, yieldable pallets and drive spring, giving another view of the parts illustrated in Fig. 4 and Fig. 5.

Similar reference numerals refer to the same parts thruout the various views.

Referring now to Fig. 1, Fig. 2 and Fig. 3, the energy of the battery B or other source of electricity is delivered to the solenoids 2 and 2, which are connected together by a magnetic bridge 3 across the back so as to form an eil ective electro-magnet, having the pole pieces at and 4 Between the poles 4: and 4; is located an iron armature 5, which is pivotally mounted at the point 6, so that it may oscillate. A cam 7 is clamped to the armature 5 by means of the screw 8, so as to oscillate with the armature and this armature member 5, 7, 8, is unbalanced relative to the pivot 6, so that when the solenoids 2, 2, are not energized the armature will drop down to the position shown in 3 of the drawings.

Coacting with the earn 7 is a cam follower consisting of a lever 10 provided with a roller on its end to engage the cam 7, which is designed to give quick positive strokes. The lever 10 by way of illustration is shown in the form of the bell crank pivoted at 11 and having an extension finger 12-the weight of this bell crank being partially supported by the spring 13. It will become apparent to those skilled in the art as the description proceeds that the particular form of this lever 1012 is immaterial and the shape shown in the drawing is only for the purposes of illustration. The function of the parts described is to transmit suitable impulses from the solenoids 2. 2 to the impulse controlling element l i, which delivers the measured impulse to the pendulum or other time determining device.

The power delivered by the cam 7, while more than ample to drive a clock mechanism, is not in a form suitable for precise regulation. In the present invention the element 1&, which determines the amount of the enp 18 meets the contact screw 31 ergy delivered to the spring 18 driving the pendulum parts, consists of a lever pivoted at 15, and arranged to be engaged by the finger 12. The lever lt may be provided with a counterweight 16 or other means for returning it to position. At the operative or driving end of the lever 14: is a pin 17 preferably a jewel, which is adapted to engage the spring 18 when the lever 14: is actuated-in which case the lever is swung to a position substantially at right angles to the spring 18, as shown in Figure 2, for reasons that will be described. I

The spring 18 is attached to the pendulum or time determining mechanism, and swings as apart thereof, so that it isperiodically brought to a position where the pin 1? may engage it. This spring 18 is the actual driving element which operates the pendulum, by

virtue of the mechanical energy stored in the spring 18 by the action of the impulse element 1a. In the preferred form the time determining element is of the pendulum type-though a balance'wheel or other equivalent device might be used-and consists of a pendulum bob 19 carried on the rod 20 suspended from the flat spring 21. The rod 20 is driven thru a crutch 22 mounted on the pivot 23. The crutch 22 is driven thru a two part verge carrying pins 24, 25, having a special construction as will be later described, and one part of this verge, such as the part carrying the pin 25 has attached to it the spring member 18, through which the driving impulses are received.

The spring member 18 preferably consists of a flat spring, and its tension and position i is adjusted by theadjusting screw 26 mounted in the rigid arm 27, which 1S secured to the verge member carrying the pin 25. Thus the spring 18, arm 27, as well as the verge crutch and pendulum proper swing as part of the pendulum element. The spring 18 car ries a contact button 30 which is adapted to make contact with the adjustable electric contact screw 81 near the end of a swing, completing a. circuit which energizes the electro-magnetic portion of the mechanism. The contact screw 31 is insulated from the frame by the insulation 32, and the electric circuit, when closed, may be traced from one terminal of the battery B thru the solenoids 2 and 2, then thru the wire 33 to the contact screw 31, contact button 30 and thru the spring 18 to the other terminal of the battery Bthe spring 18 and one terminal of the battery being grounded to the frame.

The operation of the portion of the mechanism that delivers periodic impulses to the pendulum elements will now be described, after which the manner of driving the clock will be shown. As the pendulum swings to the right, the contact button 30 in spring and closes the electric circuit described. The electro-magme es nets 4 and l are momentarily energized and attract the armature 5, rotating it into the position shown in Fig. 2 of the drawings, and rotating the cam 7 with it. This operates the cam follower and lifts the lever 10, swinging its extension 12 to the right, and moving the driving end of the element downward so that the pin 17 engages the spring 18 and forces it slightly back, breaking the electric circuit at the contact button 30. This de energizes the electromagnets 4 and t and the armature 5, and the cam and levers 7 10, 12, fall back to their original position. The element 14-, however, does not immediately fall, but is held in the position shown in Fig. 2 by the pressure of the spring 18, owing to the fact that tie impulse element 1 1 is then substantially at right angles to thedriv ing spring 18. The impulse is given the driving spring 18 by the extra flexure given it when the pin 17 swings down against it, thus storing up energy in the spring to operate the pendulum. As the pendulum swings back it absorbs this dllVlll enere' andas 2: c2. 7

it progresses the screw 26 on the arm 27 picks up the spring 18 again, and carries the spring 18 away from the pin 17, whereupon the element 14; returns to its former position.

The increment of energy is stored in the spring 18 at each vibration of the penduluin-or possibly at alternate vibrationsbut it is not necessary to store energy up for any considerable number of vibrations, as in previous constructions. It will be obvious to those skilled in the art that in place of the armature 5 being retracted by gravity, the magnetic elements may be arranged to rock the armature back and forth, so that alternate vibrations of the pendulum will receive the driving impulse. But in either event the apparatus is characterized by the fact that as soon as the motor element is retracted its driving stroke ensues on the next vibration of the pendulum, thus reducing to a min imum the period during which stored mechanical energy is retained.

The action of the impulse element 1 in relation to the driving spring 18 has several advantages, in addition to retaining itself in working position thru friction as described. It will be understood that accurate time keeping is largely dependent on delivering driving impulses of uniform strength and intensity. To do this, various diihculties must be overcome, as for example, the power of the original electro-niagnetic force will vary somewhat as the battery weakens; the initial power is relatively large and not suitable for regulation; and the mechanism must ,7

In the present invention the power is transmitted by bending the spring 18 when swingib l ing the pin 17 thru an arc whichin its later portion approaches tangency to the spring. It will be seen, therefore, that slight variations in the mechanical parts, thru wear or otherwise, will have little effect on the amount of energy actually delivered to the driving spring 18.

This method of transmitting repeated small and controlled increments of energy directly to a driving spring which oscillates with the pendulum also makes possible a method of operating a clock mechanism which has certain advantages in simplicity and accuracy. It will be recalled that in the ordinary clock the power drives the escapement wheel, and the escapement wheel drives the pendulum-the pressure of the escape ment teeth giving a slight impulse to the pendulum at each swing. In the present invention, on the contrary, the power is put in thru the pendulum and taken out thru a crown wheel 40, for example, or equivalent gear, in place of the ordinary escapementthe crown wheel being fed along tooth by tooth thru the power supplied to it by the pendulum. The driving friction in the clockwork is thus made light and uniform, with a resultant increase in accuracy and durability.

The crown wh el is rotated by the alternate engagement of the pallets 41 and 42 with the teeth or pins of the crown wheel as the pendulum swings to and fro. These pal lets have faces properly inclined to feed the crown wheel 40 around one tooth at a time. The crown wheel 40 turns the hands 43 and 44 thru the reduction gearing 45, 46, etc. of ordinary clockwork. In order to prevent possible damage to the teeth of the crown wheel 40 which might occur thru careless handling if the pallets 41 and 42 were rigidly secured to the pendulum, the pallets-are arranged so that they may yield against a spring in case of excessive stress. The pallet 41 is attached to the verge member 51 which carries the pin 24, and the pallet 42 is at tached to the verge member which carries the pin 25the members 50 and 51 being mounted on the pivot 23 and held together by the tension of the spring 52, so that the pins 24 and 25 in action resemble a crutch, connecting to the ordinary crutch 22 and the pendulum 19. The spring 52 is sufliciently strong to hold the pins 24, 25 against opposite edges of the crutch 22 in all normal operations so that the pallets 41 and 42 normally act as though they were rigid with the pendulum; but in case of an excessive accidental stress the pallets will yield before damaging a tooth.

While I have in the foregoing disclosed my invention and described it by way of illustration in a preferred embodiment, it is subject of course to various modifications as will be evident to those skilled in the art. The partieular arrangements, shape and proportions of the parts will varyto accommodate various forms of clocks, and the particular form of electric circuit is immaterial, provided it is periodically varied.

While I have explained and described my invention by certain specific examples, it will be understood that these are only by way of illustration, and that the apparatus is susceptible to various modifications and adaptaconnected to said pendulum, a verge operated by said crutch and made in two portions held together by a spring, a palletattached to each of said portions, and a toothed wheel adapted to be fed along by said pallets, the spring being suificiently strong so that in normal op erations the pallets do not yield, while in case of excessive movement of the pendulum the pallets will yield and prevent damage to the toothed wheel.

2. In a time keeping mechanism, the combination of a pendulum, a crutch for the pendulum drive, a verge connected to said crutch and comprising two parts pivotally mounted at one end and having projections which c-omprise the fork of the verge, and a spring connecting said two parts, said spring being located wholly on one side of the line of the pendulum, the strength of said spring being so proportioned that itwill hold the fork of the verge in operative position for all normal impulses of the pendulum, but in case of excessix e motion of the pendulum the spring will yield and prevent damage to the mechamsm.

3. In timekeeping mechanism, an oscillating member, a toothed wheel, a pair of spaced pallets cooperating with said wheel to control the movement thereof and interlocking with said wheel to limit the extent of each movement given said wheel, and means for urging said pallets resiliently and individually into a predetermined relation to one another and to said member for oscillation therewith and permitting individual movement of said pallets away from said member in case of excessive movement of said pendulum.

4. In timekeeping mechanism, an oscillating member, a toothed wheel forming part of a time train at the movement controlling end thereof, a pair of spaced pallets cooperating with said Wheel to drive it by fixed increments and then lock it against movement in both directions between said increments, means mounting each pallet for movement toward and from one another, and simultaneously against opposite faces of said member in all positions of said member, and means for urging said pallets yieldingly and resiliently toward one another and to clamp said member between the pallet mounting means.

5. In timekeeping mechanism, an oscillating member, a toothed wheel forming part of a time train, a pair of spaced pallets cooperating with said wheel to drive it by fixed increments and then lock it against movement in both directions between said increments, elements mounting each pallet for movement toward and from one another, said member being interposed between said elements for spaced pallets cooperating with said wheel to control the movement thereof, and means for urging said pallets resiliently and individually into a predetermined relation to one another and to said member for oscillation therewith throughout the entire arc of oscillation of said member and permitting individual movement of said pallets away from said member in case of excessive movement of said member, said urging means having such strength that in normal operations said pallets do not yield.

7. In timekeeping mechanism, an oscillating member, a toothed wheel, a pair of spaced pallets cooperating with said wheel to drive the same through uniform increments at each operation and lock the wheel against overrunning, means mounting each pallet for individual movement toward and from one another, said member being interposed between said mounting means for spacing them a desired distance apart to space said pallets, and means for urging said mounting means yieldingly and resiliently in a direction to carry said pallets toward one another to the extent permitted by said interposed member and with such force that the pallets remain in the same spaced relation to one another and oscillate with said member throughout the entire arcs of oscillations of said member, yet yield in case of excessive amplitude of oscillations of said member.

8. In timekeeping mechanism, an oscillating member, a toothed wheel, a pair of spaced pallets cooperating with said wheel to control the movement thereof and limiting the maximum movement of said wheel at each actuation, means mounting each pallet and pivoted upon a common axis for individual movement to carry said pallets toward and from one another, said member being interposed between said mounting means for spacing them a desired distance apart to space said pallets, and a spring connected between sa1d mounting means for urging said means yieldingly and resiliently toward one another to the extent permitted by said member with such force that the pallets remain in the same spaced relation to one another in normal oscillations of said member and oscillate with said member throughout the entire amplitude of oscillation of said member, yet yield in case of excessive amplitude of oscillations of said member.

9. In a time keeping mechanism the combination of a time counting train having a toothed wheel as a part thereof at the movement controlling end thereof, an oscillating time measuring element, pallet members cooperating with said wheel to impart thereto uniform increments of movement at each actuation and lock said wheel against movement in both directions between said uniform movements, and resilient means connecting said members and causing their movement together and with said element throughout the entire normal movements of said element, whereby the pressure of said pallet members on said wheel will be limited to the stress of said resilient means in the event of excessive amplitude of oscillation of said element.

10. In a time keeping mechanism, the combination of a vibrating member, a gear train arranged to keep count of the vibrations of said member, a pair of oscillating pallet elements driving said gear train and imparting thereto a uniform movement at each oscillation, said elements being resiliently connected to one another and to said member for oscillation with said member normally throughout the entire arc of oscillation of said member, whereby said pallet elements normally move with said member and impart a definite movement to said gear train under varying amplitudes of oscillation, but may yield and separate under abnormal conditions.

In witness whereof I have hereunto set my hand this 9th day of October, 1928.

ARTHUR F. POOLE. 

